The present invention relates to belt conveyors, and more particularly to such conveyors which may shift parcels ninety degrees to the direction of travel of the belts. In my U.S. Pat. No. 9,365,361, the disclosure of which is incorporated by reference herein, I showed a right-angle conveyor in which a small multibelt conveyor could be raised up between a series of rollers, to intermittently direct parcels 90 degrees to the direction of motion of the rollers.
Known belt conveyors have a plurality of flexible looped belts which have end drive rollers and in which the belts slide over supportive fixed surfaces. These belts can securely support the weight of parcels because they are entirely supported beneath, however, there is significant friction as the belts slide on the supporting surface. The side to side course of the belts can be restrained by extending through supporting channels, at the cost of additional friction and the necessity of threading the belts through the channels. These conveyors can have single looped belts which run hundreds of feet. However, the significant friction of these long runs is overcome by high torque AC motors. The tension on the long belts can be adjusted by automatic pneumatic takeup.
Conveying systems in distribution centers can extend great distances and operate nearly continuously. It is desirable to have a system which is readily maintained and serviced, and which can be arranged and configured to the present need. Moreover, it is advantageous to dispense with pneumatic systems and all their maintenance needs.